477,224 views
20 votes
20 votes
Find the sum of the infinite geometric sequence that begins 1/12, 1/18, 1/27, …

User AndySousa
by
3.5k points

1 Answer

27 votes
27 votes

Answer:

1/4

Explanation:

The sum of an infinite geometric series is given by the formula ...

S = a/(1 -r)

where 'a' is the first term, and r is the common ratio.

Application

Here, the first term is 1/12, and the common ratio is ...

(1/18)/(1/12) = 12/18 = 2/3

Then the sum is ...

S = (1/12)/(1 -2/3) = (1/12)/(1/3) = 3/12 = 1/4

The sum of the infinite series is 1/4.

User Vinay Patil
by
3.0k points